1. Field of the Invention
The present invention relates to a pneumatic tire that suppresses increase in tire mass while maintaining cut resistance and steering stability.
2. Description of the Background Art
Pneumatic tires used in vehicles for running on roads in bad conditions such as four-wheel-drive cars and trucks, may be cut at a sidewall portion due to collision with a sharp stone or the like during running on a bad road. In addition, there is a problem that the sidewall portions of the pneumatic tires are likely to be bent under heavy load acting on the tires, thereby bringing about deterioration of steering stability.
Conventionally, to cope with such problems, as shown in FIG. 8, it has been suggested a tire in which protrusions c protruding axially outwardly are provided on the outer surface of a sidewall portion “a” (refer to Japanese Patent Application Publication No. 2003-112505, for example). The protrusions c can increase cut resistance and rigidity of the sidewall portion, which leads to enhancement of steering stability.